Fatigue Measurement

The registry recorded total and subscale scores but not item-level responses. The study used validated self-administered questionnaires as proxy fatigue measures because no PCS-specific fatigue instrument was available. Pooling transformed scores improved comparability but might not preserve subtle construct differences across questionnaires. The three instruments measure cognitive and physical fatigue, with higher scores indicating more severe fatigue. Only participants assessed with FSMC, MFIS, or WEIMuS were included.